Tuesday, February 3, 2009
Which Cover Crop?
You might say I was raised with cover crops. Grandpa was a tenant farmer in Brown County and most of the income was "walked off the farm" in the form of livestock beyond meeting family needs.
The typical rotation was corn followed by wheat, interseeded with timothy and clover frost seeded in the spring. This system was used almost 100 years on that farm as dad did the same thing.
Over the years we rented extra ground for tobacco and soybeans and wheat was always seeded after that crop was harvested.
Wheat was our principal cover crop, often with Timothy and is still a good cover today. Whenever we harvest now I am thinking we should be planting a cover crop.
In 1971 I took over the Blanchester FFA School Farm as instructor and manager. There I was able to experiment with many crops and learned to no-till.
I quickly learned the value of calcium and never seemed to be able to get enough days to lime the fields. Calcium and drainage must be addressed in any good cropping system including cover crops. Cover crops just make the results even better.
In 1987 I became an Extension Agent and became involved with Warren County’s Aerial Seeding program. Cereal rye was the principal cover crop and we went through all the problems of that crop that can get out of hand in a hurry in a wet spring.
In recent years I worked with many people including Steve Groff and Leon Bird with forage or Dikon radish. I also worked with Dr. Plumer at SIU spreading the annual ryegrass story wherever I could. Today I work with these two cover crops the most.
To make it simple, I believe corn excels after radish and soybeans excel after annual ryegrass.
Cover crops need to be inexpensive to increase adaptation and neither one is cheap to buy or plant.
Still, they are well worth the investment to keep the microbes active all winter and provide decaying organic matter to feed the next crop.
Drilling 8-10 lbs of either into straw or soybean stubble is rather easy With the notill drills we have available.
Aerial seeding increases the odds of failure so we normally double the seeding rate, doubling the cost while not increasing the odds of success. Still, something is better than nothing.
Enter in Dave Brandt and his splitter planter planting one pound of radish per acre in one row while the other plants a couple of pounds of Austrian winter peas. Now you have the seed cost down but limit the acres you can cover in a rotation. This looks like an excellent system on every acre you can manage to do it.
Dry falls like the last two years insist we cover every acre with something, even wheat or rye if it gets too late to plant ryegrass or radish.
The major obstacle is not cost but physically planting two crops in one year. It is no easy challenge.
It may require you to re-tool and re-labor your operation but again it is worth it for the cash crop improvements gained.
If you only want one crop to deal with and can plant by Labor Day I would chose the radish. Their penetration value and mass of root is valuable. If you prefer grasses where you farm, ryegrass could be your choice.
The main message here is to plant SOMETHING whenever you get a fall like the last two. In 06 we couldn’t even get all the crop out without some rutting on our farm.
You are going to have years like that but don’t be discouraged. Plant SOMETHING.
I will add some important comments:
Soil test with the right soil test.
Take tissue samples of at least the cash crops at flower.
Inoculate your soybeans and inoculate your clovers or peas for maximum nitrogen production.
Inoculate your grasses and radish with a mychorizae product like T-22. I never plant without it. It greatly increases root mass and that is what we are after in cover crops, root mass.
I have spent my life learning these basic cropping principles and trust I have shared the most profitable with you